pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>org.example</groupId>
    <artifactId>mybatis-demo01</artifactId>
    <version>1.0-SNAPSHOT</version>
<parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.3.4.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
<!--    pom yml 主启动类  业务类-->
<dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
            <version>2.3.5.RELEASE</version>
        </dependency>
<dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.16</version>
            <scope>provided</scope>
        </dependency>
<dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.22</version>
        </dependency>
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>2.1.3</version>
        </dependency>
</dependencies>
</project>

application.yml

server:
  port: 8001

spring:
  datasource:
    username: root
    url: jdbc:mysql://localhost:3306/test
    driver-class-name: com.mysql.cj.jdbc.Driver
    password: 123456

mybatis:
  config-location: classpath:mybatis-config.xml

App启动类

package cn.lnfvc;


import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class App {
    public static void main(String[] args) {

        SpringApplication.run(App.class,args);
    }
}

mybatis-config.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration
        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-config.dtd">

<configuration>
    <mappers>
        <mapper resource="mapper/BookMapper.xml"></mapper>
    </mappers>
</configuration>

BookMapper.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="cn.lnfvc.mapper.BookMapper">
    <select id="findById" resultType="cn.lnfvc.pojo.Book">
        select * from book where id = #{id}
  </select>

    <select id="findAllBooks" resultType="cn.lnfvc.pojo.Book">
        select * from book;
    </select>


    <insert id="insert" parameterType="cn.lnfvc.pojo.Book">
        insert into book values (#{id},#{name})
    </insert>

    <delete id="delete" >
        delete from book where id = #{id}
    </delete>

    <update id="update" parameterType="cn.lnfvc.pojo.Book">
        update book set name = #{name} where id = #{id}
    </update>


</mapper>

Book.java

package cn.lnfvc;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
@Data
@AllArgsConstructor
@NoArgsConstructor
public class Book {
    private  Integer id;
    private  String name;
}

BookMapper

package cn.lnfvc.mapper;

import cn.lnfvc.pojo.Book;
import org.apache.ibatis.annotations.Mapper;

import java.util.List;

@Mapper
public interface BookMapper {
    Book findById(Integer id);

    List<Book> findAllBooks();

    int insert(Book book);

    int delete(Integer id);

    int update(Book book);

}

BookController

package cn.lnfvc.controller;

import cn.lnfvc.mapper.BookMapper;
import cn.lnfvc.pojo.Book;
import org.springframework.web.bind.annotation.*;

import javax.annotation.PostConstruct;
import javax.annotation.Resource;
import java.util.List;

@RestController
public class BookController {

    @Resource
    private BookMapper bookMapper;

    @GetMapping(value = "/books/{id}")
    public Book test(@PathVariable("id")Integer id){
    return bookMapper.findById(id);
    }

    @GetMapping(value = "/books")
    public List<Book> findAllBooks(){
    return bookMapper.findAllBooks();
    }

    @PostMapping(value = "/books")
    public Book insert(@RequestBody Book book){
       bookMapper.insert(book);
       return book;
    }

    @DeleteMapping(value = "/books/{id}")
    public Book delete(@PathVariable("id")Integer id){
        bookMapper.delete(id);
        return new Book();
    }

    @PutMapping(value = "/books/{id}")
     public Book update(@RequestBody Book book,@PathVariable("id")Integer id){
        book.setId(id);
        bookMapper.update(book);
        return book;
    }
}

test.http测试

POST http://localhost:8001/books
Content-Type: application/json

{"id": 5,"name": "jcl"}

###

DELETE http://localhost:8001/books/1
Accept: application/json


###

GET http://localhost:8001/books/
Accept: application/json

###

PUT http://localhost:8001/books/4
Content-Type: application/json

{"name": "456"}

###